NateHoy was a big help to me when I reworked my configuration, tweaked my WRT54GL, etc. I added a Hawking broadband booster to my setup but had horrible upload issues and as a result horrible audio problems when I was talking to folks.

While Nate's suggestions about QoS were great, I decided to take his alternate idea: disabling QoS on my WRT54GL entirely and letting the Hawking handle the QoS. Dummy me had the QoS on the WRT54GL enabled AND the Hawking connected. I'm assuming this led to some conflicts or something, because I went back and disabled altogether the QoS on the WRT54GL. Letting the Hawking device handle the QoS did the trick. (I also had previously enabled the QoS on the WRT54GL and no Hawking connected, but that didn't work well at all.)

My upload speeds went from a problematic 90k to well over 700k, and there has been a dramatic improvement in my call quality.

So, if anyone is messing around with a similar setup, I'd simply recommend you disable the QoS on your main router and use the Hawking to handle it.